Safety device for electrical circuits.



.M. H. SPIELMAN. SAFETY DEVICE FOR ELECTRICAL CIRCUITS.

APPLICATION FILED MAR. 23. 1916.

Patented D60. 4, 1917.

7 ll Z ulul I 55525 5 5:.

Q avwewfoz AW M MAXIMIIJIIIAN Hy SPIELMAN, J OF NEW YORK, N. Y.

Specification of Letters Patent.

$AFETY DEVICE FOR ELECTRICAL CIRCUITS.

Patented Dec. 4, 191 *7.

Application filed March 23, 1916. Serial No. 86,080.

To all whom it mag concern:

Be it known that I, MAXIMILLIAN H. SPIELMAN, a citizen of the United States, and a resident of the borough of Manhattan in the city, county, and State of New York,

have lnvented certain new and useful Improvements in Safety Devices for Electrical Circuits, of which the following is a description in such full, clear, and exact terms as will enable any person skilled in the art to which it pertains to make and use the same.

My invention is adapted to be used in connection with burglar alarms on windows, doors and the like and indeed in any other situation where the circuit is to be controlled by the position of a sliding or reciprocating part.

Considered in its location as a burglar alarm attachment for windows its object is to allow the window to be open for ventila tion a certain extent without sounding the alarm but to sound the alarm should the window be further opened.

To this end it comprises certain novel features of construction to be set forth and particularly pointed out in the claim.

Reference is now had to the drawings in which- Figure 1 is a sectional elevation of the invention.

Fig. 2 is a detail section on the line 2-2 of Fig. 3.

Fig. 3 is a detail section on the line 3-3 of Fig. 1.

Fig. 4 is a detail section of a modification.

Referring to Figs. 1, 2 and 3, (4 indicates the upper sash and 6 indicates the lower sash of the usual window with a parting rail between them. My improved safety device is let into the parting rail and has a housing comprising a front plate 10 and side walls 11. The front plate is secured to the parting rail by screws or the like and the side walls project into a cavity into the parting rail. The parting rail is formed with recesses 12 and the side walls 11 of the housing are similarly recessed to accommodate contact fingers 14. These have one end projected through the recesses 12 so that they engage respectively the side rails of the sashes a and b which side rails have sliding contact with the fingers 14 as the sashes are moved up and down. This movement of the sashes causes the contact fingers to throw back and forth in the recesses 12 within the limits of said recesses.

The contact fingers 14 are pivotally mounted on spring arms 15 and said arms in turn are coiled or otherwise fastened around studs 16 which are secured in an insulation back plate 17 held between the side walls 11 of the housing. The arms 15 are connected with each other electrically as well as mechanically and they are also electrically connected with the swinging fingers 14; One of the studs 16 passesthrough the insulation block 17 and at the rear is adapted to have connection with theelectric cir-' cuit as indicated at 18. 19 indicates two pins which project forward from the insulation block 17 in the path of the swinging fingers 14 and when either one or both of said fingers are swung toward each other from the position in Fig. 2 they contact with said fingers 19 and either one or both of these contacts will serve to close the electrical circuit since said pins 19 are joined together electrically by a connection 20 at the back of the block 17 and this in turn is joined by connection 21 with the remainder of the electrical circuit.

Now when the parts stand as in Figs. 1 to 3 the circuit is open because to close the cirsuit it is necessary for one or both of the arms 14 to contact with its corresponding pin 19. Assuming that Fig. 1 indicates the sashes when both of them are closed, now it will be seen that if the upper sash is moved downward to open it or the lower sash is moved upward to open it, it will cause the corresponding arm 14 to swing into contact with the pin 19 and then circuit will be closed and will set off the alarm. But the alarm may be instantly checked by giving the sash a slight closing or return move ment suiiicient to throw the arm 14 out of engagement with its pin 19 and thereby break the circuit. But the sash need not be returned to closed position and may be left open the desired degree for ventilation or the like. Now should any one open the sash still further to effect, for example, an entry in the apartment it is clear that the arm 14 will be instantly moved down again into contact with its pin 19 closing the circuit and setting off the alarm. This operation is present on both of the sashes owing to the provision of a swinging arm 14 for each sash and it operates according to the same principle on the lower sash. The sash being iven a very slight closing movement after it is opened which moves the arm 14 back from its pin 19 and sets the parts so that the alarm does not sound but the instant the sash is further opened it will. sound.

Fig. 4 shows a slight modification of the construction shown in Figs. 1 to 3 according to which the arms 14 carry rollers 22 which engage the sashes and these rollers swing back with the arms to engage contact fingers 23 and thereby close the circuit. The principle of operation is exactly the same so too with the arrangement of the connections and other details.

It will be seen in reference to Fig. 4 that the same result is obtained as with the construction shown in Figs. 1 to 3; the window is opened slightly beyond the desired extent and then moved back very slightly toward closed position. This breaks the circuit of the alarm but the instant the window is opened further the circuit is closed and the alarm is given.

Having thus described my invention What I claim as new and desire to secure by Letters Patent of the United States, is

The combination with a frame or housing of contact fingers pivotally mounted on spring arms which are coiled around studs secured to a back plate held between the side walls of the housing, and contacts in the housing adapted to be engaged respectively by the contact fingers upon the swinging of one or the other thereof for the purpose specified.

In testimony whereof I have hereunto signed my name in the presence of two witnesses.

MAXIMILLIAN H. SPIELMAN. Witnesses:

ISAAC B. OWENS, ETHEL S. HUGHES.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. 0. 

